Question:

I got this code P0133 rear oxygen sensor not switching. Since this car has too many miles, I decided to change the rear oxygen sensor including the CAT (catalytic converter). After doing all of these, the check engine light returned with the same code. I am now thinking of replacing the ecm (computer) but since it is too expensive, I want to ask your opinion.

ATS Adviser:

You can replace the ecm as long as you do these:

check all the ground connections for this engine using ATS wiring diagrams. Once you clean all the ground wires, reset the code and take it for a road test and see if the code goes away. If not…

check the ecm ground voltage readings with key on engine off. It must not exceed 0.250 volt. Higher reading means a fault in the wirings or component like sensors. You can also check for reference voltage (usually 5 volts) at pin 59 which is a good indicator if your ecm is good or not. Otherwise, replace the ecm but open it up and check for signs of burnt or heated electrical circuits.

This entry was posted on Tuesday, February 20th, 2007 at 3:55 am and is filed under Check Engine Light FIXES. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.